1. Related Field of the Present Invention
This invention relates to a stomach exercise device, and particularly to a pneumatic stomach exercise device having an air cylinder incorporating a piston and mounted on a base by means of a universal joint, the base being used to be positioned beneath the two thighs of the exerciser while the exerciser is sitting.
2. Brief Description of Related Prior Art
In common practice, people exercise their stomach by twisting to and fro or alternately bending and straightening at the waist. Various exercise devices are available for stomach exercises. Some of them are used for a twisting exercise and some are used for a bending and straightening exercise.
A common stomach exercise device is one which is comprised of extension springs. In operation, the user sits, positions one end of the device at his/her legs and holds the other end to alternately pull the springs and let them return by their resilient forces. This operation causes the user to alternately bend at the waist and straighten his body. A disadvantage of this device is that the device does not permit the user to vary its use according to his physical condition.